May A. Beydoun

Will All Americans Become Overweight or Obese? Estimating the Progression and Cost of the US Obesity Epidemic

We projected future prevalence and BMI distribution based on national survey data (National Health and Nutrition Examination Study) collected between 1970s and 2004. Future obesity‐related health‐care costs for adults were estimated using projected prevalence, Census population projections, and published national estimates of per capita excess health‐care costs of obesity/overweight. The objective was to illustrate potential burden of obesity prevalence and health‐care costs of obesity and overweight in the United States that would occur if current trends continue. Overweight and obesity prevalence have increased steadily among all US population groups, but with notable differences between groups in annual increase rates. The increase (percentage points) in obesity and overweight in adults was faster than in children (0.77 vs. 0.46–0.49), and in women than in men (0.91 vs. 0.65). If these trends continue, by 2030, 86.3% adults will be overweight or obese; and 51.1%, obese. Black women (96.9%) and Mexican‐American men (91.1%) would be the most affected. By 2048, all American adults would become overweight or obese, while black women will reach that state by 2034. In children, the prevalence of overweight (BMI ≥ 95th percentile, 30%) will nearly double by 2030. Total health‐care costs attributable to obesity/overweight would double every decade to 860.7–956.9 billion US dollars by 2030, accounting for 16–18% of total US health‐care costs. We continue to move away from the Healthy People 2010 objectives. Timely, dramatic, and effective development and implementation of corrective programs/policies are needed to avoid the otherwise inevitable health and societal consequences implied by our projections.

Is Sleep Duration Associated With Childhood Obesity? A Systematic Review and Meta-analysis

Obesity is a major public health epidemic worldwide in children and adults (1–6). The prevalence and severity of childhood obesity is dramatically increasing with a corresponding increase in the prevalence of obesity-related morbidities particularly those involving obstructive sleep apnea and metabolic and cardiovascular seque-lae (7). Prevention of childhood obesity is an urgent issue for public health, in par-ticular, in many industrialized countries and some transition societies. Nutrition and physical activity (PA) have been the major research focus on obesity preven -tion (8–11). However, most published findings of such interventions suggested little success in preventing childhood obe-sity (6,12), although some that focused on dietary or/and PA approaches have showed some desirable impact on BMI status (13). Other risk factors, such as sleep, may be related to obesity, although sleep behavior has received much less attention than dietary intake and PA (14,15).Sleep, like PA and diet, plays an impor-tant role in the growth, maturation, and health of children and adolescents by allowing for the diurnal rhythm of hor -mones related to growth, maturation, and energy homeostasis (16). A number of biological mechanisms have been pro -posed to link sleep duration and obesity (17). For example, one theory posits that children with short sleep have low caloric intake and expenditure, given that sleep deprivation often leads to changes in the structure of sleep stage and results in fatigue, daytime sleepiness, somatic and cognitive problems, and low activity lev-els (18,19). Previous studies indicate that sleep deprivation results in changes in lev -els of several hormones including leptin, ghrelin, insulin, cortisol, and growth hor-mone (20–22). These hormonal changes may contribute to energy imbalance and then lead to overweight or obesity.Recently, there is increasing epide-miological evidence suggesting a link between sleep duration and obesity in children (18,23–26), adolescents (27), and adults (28–30). In adults, some studies indicate a negative association between sleep duration and obesity/BMI in men and a U-shaped relation between sleep duration and BMI in women (29). Several epidemiological studies have examined the association between short sleep duration and obesity in children and adolescents (18,23–27,31–37), but the reported findings are inconsistent (18,32,35,37). A recent review summa-rized 13 studies that examined the asso-ciation between short sleep duration and obesity among children and adolescents, and recommended more sleep to pre-vent obesity (17). However, the review suffered from several limitations includ-ing misclassification of the design of some studies and included a study with adults as the primary age group (28). Several related previous studies were not included. Furthermore, new studies have been reported since the publication of the review. A major gap in the related litera-ture is that to our knowledge, no meta-analyses have been conducted to examine the overall association quantitatively and to test the possible differences by popula-tion groups such as age and gender.This study aimed to assess epidemio-logic evidence systematically on the relation between sleep duration and childhood obesity. We first performed a systematic review of all related studies and then conducted a meta-analysis based on cohort studies and cross-sectional studies in the general pediatric population.

Obesity and central obesity as risk factors for incident dementia and its subtypes: a systematic review and meta-analysis

While dementia affects 6–10% of persons 65 years or older, industrialized countries have witnessed an alarming rise in obesity. However, obesitys influence on dementia remains poorly understood. We conducted a systematic review and meta‐analysis. PUBMED search (1995–2007) resulted in 10 relevant prospective cohort studies of older adults (40–80 years at baseline) with end points being dementia and predictors including adiposity measures, such as body mass index (BMI) and waist circumference (WC). There was a significant U‐shaped association between BMI and dementia (P = 0.034), with dementia risk increased for obesity and underweight. Pooled odds ratios (OR) and 95% confidence intervals (CI) for underweight, overweight and obesity compared with normal weight in relation to incident dementia were: 1.36 (1.07, 1.73), 0.88 (0.60, 1.27) and 1.42 (0.93, 2.18) respectively. Pooled ORs and 95% CI for obesity and incident Alzheimers disease (AD) and vascular dementia were 1.80 (1.00, 3.29) vs. 1.73 (0.47, 6.31) and were stronger in studies with long follow‐up (>10 years) and young baseline age (<60 years). Weight gain and high WC or skin‐fold thickness increased risks of dementia in all included studies. The meta‐analysis shows a moderate association between obesity and the risks for dementia and AD. Future studies are needed to understand optimal weight and biological mechanisms.

Intimate partner violence against adult women and its association with major depressive disorder, depressive symptoms and postpartum depression: a systematic review and meta-analysis.

To date, few systematic reviews of observational studies have been conducted to comprehensively evaluate the co-morbidity of intimate partner violence (IPV) and specific depression outcomes in women. In this systematic review and meta-analysis, we summarize the extant literature and estimate the magnitude of the association between IPV and key depressive outcomes (elevated depressive symptoms, diagnosed major depressive disorder and postpartum depression). PubMed (January 1, 1980-December 31, 2010) searches of English-language observational studies were conducted. Most of the selected 37 studies had cross-sectional population-based designs, focused on elevated depressive symptoms and were conducted in the United States. Most studies suggested moderate or strong positive associations between IPV and depression. Our meta-analysis suggested two to three-fold increased risk of major depressive disorder and 1.5-2-fold increased risk of elevated depressive symptoms and postpartum depression among women exposed to intimate partner violence relative to non-exposed women. A sizable proportion (9%-28%) of major depressive disorder, elevated depressive symptoms, and postpartum depression can be attributed to lifetime exposure to IPV. In an effort to reduce the burden of depression, continued research is recommended for evaluating IPV preventive strategies.

Recurrent depressive symptoms and the incidence of dementia and mild cognitive impairment

Objective: A history of depression has been linked to an increased dementia risk. This risk may be particularly high in recurrent depression due to repeated brain insult. We investigated whether there is a dose-dependent relationship between the number of episodes of elevated depressive symptoms (EDS) and the risk for mild cognitive impairment (MCI) and dementia. Methods: A total of 1,239 older adults from the Baltimore Longitudinal Study of Aging were followed for a median of 24.7 years. Diagnoses of MCI and dementia were made based on prospective data. Participants completed the Center for Epidemiologic Studies Depression Scale at 1- to 2-year intervals and were considered to have an EDS if their score was ≥16. Kaplan-Meier survival curves, log-rank test for trend for survivor functions, and Cox proportional hazards models were conducted to examine the risk of MCI and dementia by number of EDS. Results: We observed a monotonic increase in risk for all-cause dementia and Alzheimer disease as a function of the number of EDS. Each episode was associated with a 14% increase in risk for all-cause dementia. Having 1 EDS conferred an 87%–92% increase in dementia risk, while having 2 or more episodes nearly doubled the risk. Recurrence of EDS did not increase the risk of incident MCI. Conclusions: Our findings support the hypothesis that depression is a risk factor for dementia and suggest that recurrent depression is particularly pernicious. Preventing the recurrence of depression in older adults may prevent or delay the onset of dementia.

How do socio-economic status, perceived economic barriers and nutritional benefits affect quality of dietary intake among US adults?

Background:Socio-economic factors may affect diet quality, perhaps differentially across gender and ethnicity. The mechanism of this association is still largely unknown.Objectives:We examined the independent effects of socio-economic status (SES), perceived barrier of food price (PBFP) and perceived benefit of diet quality (PBDQ) on diet quality indicators and indices (DQIj,k), across gender and ethnicity. Additionally, we estimated the mediation proportion of the effect of SES on DQIj,k through PBFP and PBDQ.Methods:Data from two cross-sectional surveys, the Continuing Survey of Food Intakes by Individuals (CSFII) and Diet and Health Knowledge Survey (DHKS) 1994–96 were used. Our sample consisted of 4356 US adults aged 20–65 years. With principal components analysis, SES (an index) was measured using household income per capita and education, and PBDQ was measured using an 11-item scale. PBFP was defined as the ratio of importance of food price score relative to nutrition. DQIj,k were assessed by a set of indicators and two indices including the Healthy Eating Index.Results:The associations between SES, PBFP, PBDQ and DQIj,k varied significantly across gender and ethnic groups. PBFP acted as a mediator in the association between SES and selected DQIj indicators, namely energy, fat intake, sodium and simple sugar consumption (mediation proportion >10%), but not PBDQ.Conclusions:SES, PBFP and PBDQ all affect dietary intake, and vary by ethnicity and gender. Positive effect of SES on DQIj,k may be mediated by PBFP but not PBDQ which is an independent protective factor. Nutrition education is important to promote healthy eating.

The association of fast food, fruit and vegetable prices with dietary intakes among US adults : Is there modification by family income?

We examined the effects of prices of fast foods and fruits and vegetables on dietary intake, body mass index (BMI) and obesity risks and whether the associations varied across groups according to their family income. Data from the US Department of Agriculture Continuing Survey of Food Intakes by Individuals (CSFII 1994-96) for 7331 individuals aged 20-65 years with complete data on two 24-h recalls were used. We computed two food price indices (FFPI and FVPI) which were linked to individuals through geocoded identifiers. Main outcomes included dietary intakes of energy, selected nutrients and food groups, fast food consumption, and diet quality measured using two indices (HEI and aMED), BMI and obesity. Interaction terms between key variables were tested in regression analyses and in further stratified analysis by family income. Higher fast food price indices (FFPIs) were associated with higher fiber intake, lower saturated fat, and better overall diet quality as measured by aMED. FVPI was positively associated with improved dietary quality as well as in terms of lower cholesterol and sodium intakes, improved HEI and lower BMI. Most of these associations showed homogeneous strengths across income groups as evidenced by a non-significant FFPIxPIR or FVPIxPIR interaction term (p>0.10). While increasing FFPI by 1 standard deviation was only borderline protective against fast food consumption, its association with other binary outcomes that were considered was non-significant. In contrast, FVPI was protective against obesity, particularly among the near poor. It was also associated with improved aMED score. Analyses of these national data suggest that changing fast food and fruit and vegetable prices may affect peoples dietary quality and to some extent their adiposity, although the present study is limited by the available food price data.

Do children and their parents eat a similar diet? Resemblance in child and parental dietary intake: systematic review and meta-analysis

Objectives Parents are believed to have a strong influence on childrens eating behaviours. However, previous findings on child–parent resemblance in dietary intakes are mixed. We systematically reviewed and meta-analysed the association (correlations) based on published studies. Methods We searched related studies published since 1980 and found 24 studies meeting inclusion criteria for review and 15 for meta-regression analysis. We compared the associations between parent–child pairs, nutrients, over time and by dietary assessment method. Results Most studies were based on small samples. Overall, they suggest a moderate or weak association, but findings varied remarkably. Our meta-analysis showed that average Fishers transformed correlations were 0.20 (95% CI 0.13 to 0.28) for fat (% energy); for energy, 0.21 (0.18 to 0.24). The correlations varied by parent–child pairs, dietary assessment and countries. Food frequency questionnaires or mixed approaches yielded lower correlation than 24-h recalls or food records. Child self-reported intakes showed weaker correlation and better methodology quality showed stronger correlation in fat intake (% energy), which also became weaker over time. Conclusions Overall, the resemblance is weak, and it varied considerably across studies, nutrients, foods and parent–child pairs.

Parent-child dietary intake resemblance in the United States: Evidence from a large representative survey

We studied the association in dietary intakes and patterns between parents (aged 20-65 years) and their children (aged 2-18 years), using nationally representative data collected by the US Department of Agriculture (USDA) in the Continuing Survey of Food Intake by Individuals 1994-96. We analyzed two 24-h recall dietary data for 1061 fathers, 1230 mothers, 1370 sons and 1322 daughters. All analyses adjusted for sampling design complexity. We assessed multivariate-adjusted parent-child correlations in selected nutrients, food groups and overall dietary quality assessed using the new USDA 2005 Healthy Eating Index score (HEI(n)). The parent-child correlations were weak or moderate (0.20-0.33) for most intake measures. There were clear patterns of interaction with gender dyads in the intakes of calcium and dairy products (P<0.05 for dyadxparental intake), whereby multivariate-adjusted correlations in mother-daughter or mother-child dyads were significantly stronger compared to their father-child counterparts. The reverse was true for multivariate-adjusted correlations in HEI(n). Hispanics and other ethnic groups had significantly stronger resemblance than Non-Hispanic whites and blacks in soft drinks and HEI(n). Resemblance in general was stronger among older children, though the reverse was true when considering agreement in HEI(n)s upper quintile. The influence of family income and parental education on the resemblance was small. In conclusion, parent-child dietary resemblance in the US is relatively weak, and varies by nutrients and food groups, and by the types of parent-child dyad and population groups. Factors other than parental eating behaviors seem to play an important role in affecting American young peoples dietary intake.

Serum Antioxidant Status Is Associated with Metabolic Syndrome among U.S. Adults in Recent National Surveys

Potential antiinflammatory and antioxidant effects were recently ascribed to naturally occurring micronutrients. The extent and magnitudes of their differential effects on the metabolic syndrome (MetS) are still unknown. We examined the association between serum antioxidant status and MetS. NHANES 2001-2006 cross-sectional data among adults aged 20-85 y were analyzed (n = 3008-9099). MetS was defined with the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) and also by elevated homeostatic model assessment insulin resistance (HOMA-IR), C-reactive protein (CRP) and hyperuricemia. Serum antioxidants included retinol, retinyl esters, carotenoids [α-carotene, β-carotene (cis+trans), β-cryptoxanthin, lutein+zeaxanthin, total lycopene], vitamin E, and vitamin C. MetS (NCEP ATP III) prevalence in U.S. adults was 32.0% among men and 29.5% among women. Adults with MetS had consistently lower serum carotenoid concentrations compared with those without MetS, even after controlling for total cholesterol and TG among other potential confounders. Vitamin E had no significant relationship with MetS in the full multiple logistic regression model, whereas retinol+retinyl esters were inversely related to MetS among men only. The latter were also inversely related to elevated CRP and positively associated with hyperuricemia. Vitamin C exhibited a similar pattern to serum carotenoids with an inverse linear association with MetS (binary), HOMA-IR, and hyperuricemia. Future intervention studies of dietary and lifestyle change must be conducted to assess the utility of modifying serum antioxidant concentrations, especially carotenoids, given their suboptimal levels among U.S. adults with MetS, for the prevention of type 2 diabetes and various cardiovascular endpoints.